1. Field of the Invention
The present invention generally relates to a method of dispatching semiconductor batch production, in particular with respect to a relationship between a line width bias of semiconductor product and machine, in order to eliminate the various variations during the manufacturing process.
2. Description of the Related Art
A line width is not only one of the important quality characteristics among the semiconductor elements, but also the significant index in the process thereof. The line width is generally defined as the smallest width of two patterns on a wafer, and with the more and more precision of semiconductor process being, if stacking a multi-layer structure on a tiny field or conducting numerous etching, even a slight bias generated by size and distance among the elements may easily be enlarged and cause deficiency, which not merely affects the schedule of the relevant manufacturing process, but also results in a great loss to the factory due to the semiconductor process such as etching process is unable to reproduce and the unqualified products have to scrap.
The general reason for causing line width bias lies in many possibilities. The present management of line width of semiconductor product mainly aims at adjusting the diversity of each machine, such as the setting of parameter of equipment for etching duration, gas flow, and electric quantity variation and so on; however, the arrangement often needs to be adjusted by experienced technician, and the adjusted machine does not fit into each batch productions, at the same time, engineering department cannot engage with manufacturing department due to the arrangement for setting the machine, so that the worker is incapable of proceeding to dispatch in accordance with the status of machine, and thus the line width bias of the products still continue to produce.
In view of the attribution, which may affect the line width, mainly includes product category, chamber, measuring machine, processing duration and relevant operation parameter of machine and so on. After gathering the historical data and conducting an analysis on the relevance, it can be found that the product category, the processing machine or the chamber have a higher relevance with the line width bias, consequently, in order to resolve the problem of causing a line width bias of semiconductor products, the variation of product category or reaction to machine are the most serious influences which needs to be embarked on.
As a result, a method of dispatching semiconductor batch production is provided to designate an adequate production machine by measuring the similarity of the line width bias between each batch productions and machines to overcome the aforementioned technical obstacle, so that to increase a higher production yield rate.